In six pedigrees with a familial predisposition to keloid formation the pattern of inheritance suggests a dominantly inherited disease due to a single autosomal gene. As a first step in identifying the gene(s) responsible for the disorder in these families, we will perform a systematic analysis of their genomes using simple sequence repeat polymorphisms. DNA will be extracted from blood of affected and unaffected family members and used as template for PCR with primers for polymorphic chromosomal markers. EBV-transformed lymphoblasts will also be cultured from selected affected and unaffected individuals and used as source of mRNA for PCR amplification of cDNAs for candidate genes. LOD scores will be calculated using standard programs. Candidate genes will be evaluated by testing of intragenic polymorphic markers, SSCP analyses, and cycle sequencing of cDNA amplified form EBV-transformed lymphoblasts.